A table saw typically includes a flat, horizontally oriented table having an opening formed therein through which a top portion of a circular saw blade protrudes. The saw blade may be 10-12 inches in diameter, for example, and is motor driven to rotate at a speed of 3,000 revolutions per minute or more. A piece of stock material, typically wood, may be cut by moving it across the table to intersect the spinning saw blade. The height of the top of the saw blade above the table may be adjustable within predetermined limits in order to accommodate stock material of various thicknesses.
A fence is provided with a table saw to guide the movement of the stock in a direction parallel to the plane of the saw blade in order to ensure a straight cut and to avoid binding of the non-cutting portions of the saw blade within the stock material. A fence typically includes an elongated metal bar having a flat guide face oriented at a right angle with respect to the table and parallel to the plane of the saw blade. The distance between the fence guide face and the saw blade may be adjustable within predetermined limits in order to accommodate stock material and cut locations having various widths.
It is known to use a push stick to urge the stock material past the saw blade in order to keep the operators fingers at a safe distance from the dangerous rotating blade. The most simple push stick may be simply an elongated piece of excess stock material that is urged against the work piece. A more sophisticated push stick is described in U.S. Pat. No. 6,135,521 as including an ergonomically designed handle, two stepped portions for engagement with the work piece, and non-slip pads for better control. While the push stick of the '521 patent does provide a degree of protection for the one hand of the operator, it still requires the operator to touch the work piece with a second unprotected hand. Furthermore, this style of push stick can apply downward force against only the trailing edge portion of the work piece since it engages the rear edge of the work piece with a stepped portion of the stick. Applying downward force only against the trailing edge portion of the work piece may be inadequate to hold the stock material down. A long piece of stock material being urged into a saw blade with such a tool may be lifted away from the table by the lifting action of the rotating saw blade, thus creating a dangerous kick-back condition where the work piece is thrown upward toward the table saw operator.
U.S. Pat. No. 2,839,100 describes a woodworking accessory that engages the work piece along an extended length in order to keep the operator's hands away from the saw blade at all times. This device engages the stock material with a plurality of screws, thus causing undesirable damage to the work piece. While this device provides improved control of the work piece between the saw blade and the fence guide face, it does not provide any control for the severed portion of the work piece on the far side of the blade away from the fence, commonly called the outside cut material. While the outside cut material is often considered the scrap portion of the stock material, it nonetheless may present a danger to the operator if it is not properly restrained during the cutting operation.
U.S. Pat. No. 4,370,909 describes a hand guard for a table saw including a grooved underside adapted to rest on top of the work piece and a vertically moveable heel for engaging the rear edge of the work piece. Here, again, this tool engages the stock material only near its rear edge and is thus ineffective in restraining the leading edge portion of a long piece of stock material. Furthermore, the tool is narrow and must be positioned against the guide fence, so it is useful for removing only a small width of material from the work piece. The tool is designed to exert a pushing force against the work piece. It includes no means for positively forcing the work piece against the guide fence, thus necessitating the use of the operator's second unprotected hand for maintaining pressure against the fence as the work piece is moved past the saw blade.